Improvement in fire-escapes



vrrnn STATES PATEN THOMAS P. FORSYTH, NEW HAVEN, PENNSYLVANIA.

lMPROVEMENT IN FIRE=ESCAPES.

Specifcation formin g part of Letters Patent No. 161,]13, dated March23, 1875; application filed January 26, 1875.

.To all whom itmay concw:

Be it known that I, THOMAS P. FoRsY'rH,

' of New Haven, in the county of Fayette and is a clamping lever or jaw,showing in dotted lines the pivoted bit or clamping piece. Fig. 3 is asectional view of a jaw, showing the manner of securin g the detachablebits rigidly to the clamping-jaw, and also the manner of adjusting thebits. Figs. 4:, 5, 6, 7, and 8 are detached views of pivoted and fixedclamping .pieces or bits, showing some of the various orms which may begiven to the faces of the Like letters refer to like parts whenever theyoccur.

My invention relates to that class of articles known as fire-escapes orclamps for ascending or descending a rope or cable and it consists,first, in forming the jaws or clamping-levers with detachable andadjnstable bits or clamping pieces pivoted or otherwise attached to thejaws, so as to adjust themselves to the rope; secondly, in detachablebits or clamping pieces, which can be rigidly secired to the clampingjaws or leversby means of setscrews or similar suitable devices, wherebythey may be changed at will to obtain variousshaped clamping-surfaces;thirdly, in providing the clamp with loops, straps, or similar deviceswhereby the clamp is Secured to the hand, and may be readily opened andclosed;

fourthly, in providing the stirrup with a slide or similar device,whereby the stirrup may be readily Secured to the foot.

Fire-escapes or clamps for ascending or descending ropes, as at presentconstructed depend upon the shape of the clamping-surfaces for theirhold upon the rope, and in general are of such form as to bend thehempen or similar rope from a right line. While this is practicable witha flexible rope and gives all the gripe required, it is evident thatwhere a wire-rope is to be employed the present devices will onlypartially meet the requirements, because, as the ropevwill notaccommodate itself to the inequalities of the clamping-surface, theclamping-levers cannot be brought sufficiently close together to bereadily managed and controlled; and, fnrthermore, the inequalities ofthe rope and clamp interfere with the sliding movement in descending andwork njury to both clamp and rope. As wire-rope is conceded to be themost suitable-for fire-escapes, whether permanently or temporarilyattached to buildings, it is the object of this invention to soconstruct the clamping devices that they may be readily adapted for useeither with wire or other rope, as necessity or desire may dictate.

Iwill now proceed to describe my invention so that others skilled in theart may apply the same.

A and A' represent the two clamping jaws or levers, which may be usedtogether to form the clamp. The jaw A may be slotted at a to engage withthe pivot a upon the end of jaw A', or the two jaws may be pivoted inthe usual way. Instead of making the clamp or biting surface directly onthe face of the jaw A', as heretofore, I pivot to the jaw,by a pivot, b,or other suitable means, a separate detachable bit or cam, B, which,from its manner of attachment to the lever A', is at liberty to adjustitself to the surface 'against which it is brought. The face b' of thisbit or cam B .will

vary in form according to requirements, and, if made of metal, may bechilled or case-hardened, if desired. For use with wire-rope it ispreferably grooved longitudinally, as shown in Fg. 8. The clamping leveror jaw A is formed with a recessed or countersunk portion, a for thereccption of the detachable clamping piece or bit B', which is heldfirmly in place by a set-screw, G, and is adjusted by set-screws e chearing against the under face of the bit B', so that the clamp may beadapted to wire or other ropes of varying sizes. This bit B' may be of a'shape to conform with bit B, or plan, if desired, and when of metal maybe chilled or case-hardened upon its face the same as B. D is awrist-loop Secured to the jaw A, and provided with a slide or similardevice, d, whereby the clamp may be attached to the user in such amanner as to obviate any liability of its being dropped. Both of theclamping -jaws A A' are provided with straps e e, secured to the clampsby rivets l or otherwise, and having bucklesf, to enable the loop formedby the strap to be enlarged or contracted at plea-sure. Through thesestraps the thumb and back of the hand are passed, and the clamp is thenunder the control of the user, so that it may be opened or closed inclimbng. The stirrup E is also provided with a slide, i, for narrowingthe loop and securing the stirrup to the foot. r

In the drawings the detachable pivoted clampingsurface is shown attachedto one jaw only, and the detacha'ble piece secured by a setscrew toanother of two jaws, which, taken together, form the clamping device;but it is evident that the clamping surfaces or bits may be bothpivoted, thereby fulfilling one essential of this intentiontheadjustability of the clamping surfaces--or may be Secured to the jaw byset-screws, thereby fulfilling another essential of my invention-viz.,changeable surfaces to adapt the clamp to the rope used-but in general Iprefer to use one fixed bit and one pivoted bit.

Figs. 4, 5, and 6 show forms of the bit-s that may be used with flexibleropes, while Fig. 7 corresponds to those shown in Figs. 2 and 3, and areplain-faced hits, or may be grooved longitudinally, and are adapted moreespecially for use with wire-ropes, rods, &0.

The two jaws A and A' being joined either by a key or pivot, or by theslots w in A engaging with lugs a on jaw A', the bit or cam B will enterbetween the projecting flanges a? upon jaw A, and the rope will begriped between the faces of B and B'. The pivoted bit B being at libertyto adjust itself to the line of the rope will allow the jaws A and A' tobe brought closely together, so as to be readily controlled by theoperator. The pieces B and B' may be renewed or changed at pleasure.

The clamps may be provided with stirrup and body belt, as described inLetters Patent No. 155449, granted to me September 22, 187 4.

In using the devices above described, the clamp is Secured to the personby slipping the hand through the wrist-loop D and pressing-the slide ddown, after which the thumb and hand are passed under the straps eattached to the clamps. This gives the user full control of the clamp.The feet are secured in the stirrup by means of the slide upon thestirrup. The devices may be used for climbing by sliding them along therope alternately and shifting the weight of the person from one clamp tothe other, or a single clamp may be used in descending. In the lattercase, if additional weight than that of the user is to be carried, thelevers or arms of the clamp should be made proportionably long andstrong.

Having thns described my invention, what I claim, and desire to secureby Letters Patent, is-

1. The pivoted clamping piece or bit, in combination with theclamping-levers, and pivoted thereto, substantially as and for thepurpose specified.

2. In combination with the clamping-levers, a detachable clamping pieceor bit capable of being rigidly attached to the clampingleve',substantially as and for the purpose specified.

3. A clamping-level', provided with a pivoted clamping piece or bit, incombination with a clampinglever having a detachable bit capable ofbeing rigidly secured to said lever, substantially as and for thepurpose specified.

4. In combination with clamps A, the strap D, substantially as and forthe purpose specified.

5. The stirrup E, provided with the slide z', substantially as and forthe purpose specified.

In testimony whereof I, the said THOMAS P. FORSYTH, have hereunto set myhand.

THOMAS P. FORSYTH.

Witnesses:

A. B. HOSACK, JOHN KURTZ.

